Students at Drexel Avenue School form lines while entering the school on the first day of classes in Westbury. (Aug. 30, 2012) Photo Credit: Newsday / J. Conrad Williams, Jr.

The back-to-school routine will vary for thousands of Long Island public school students next month as districts across both counties split on when to hold the first day of class.

Students return on Monday, Sept. 9, in at least 65 of Long Island's 124 districts. Students in more than 30 districts will start Tuesday, Sept. 3, and attend school on Sept. 4 before being off for two days for the Jewish holidays of Rosh Hashanah. About 20 other school districts return for one day on Sept. 4 and then are off again until Sept. 9. Labor Day falls on Sept. 2.

Many districts have built in staff conference days before the opening of school.

In the Mattituck-Cutchogue district, the staff will return on Sept. 3 for two conference days and then the district will close until Sept. 9, when the students start.

"We have historically in the last couple of years had two conference days at the beginning of the year and we have found this is very beneficial," Superintendent James McKenna said. "It seemed ridiculous to come in and bring in kids for a day and then close for the Jewish holidays. It didn't make logical sense."

Some schools that have the earlier start dates will have teachers and staff report at the end of August for conferences. Garden City students return to school Sept. 3, but staff will report to the district on Aug. 28 and 29. The district has 184 days of instruction scheduled for the 2013-14 school year.

Kings Park students return on Sept. 3, and Superintendent Susan Agruso said that fallout from superstorm Sandy is part of the reason why. Many districts across Long Island, including Kings Park, canceled all or part of the February break to make up time lost after the Oct. 29 storm forced many schools to close for days.

"We wanted to maximize available makeup days at the end of the school year. We don't want to take a chance running into the February problem that we had this year," she said. "We added time to spring break and Memorial Day. If we do have serious weather conditions we are prepared for them."

Officials with the state Department of Education said that state law requires 180 days of school, but scheduling is a local matter.

In Lindenhurst, students return Sept. 9 and classes run until June 27, Superintendent Richard Nathan said.